Method and apparatus for estimating a seed germination ability

Abstract

An apparatus and method for estimating a germination ability of a seed includes a terahertz signal source for emitting a terahertz signal towards the seed, a detector for detecting at least part of the terahertz signal having interacted with the seed, a scanner for moving the support relative to the terahertz signal to provide a scan of the seed, a data processing device for forming an image data from the detected terahertz signal as obtained for a plurality of positions during the scan of the seed, and a decision support system for providing an estimate of the germination ability from the image data. In an embodiment, the terahertz signal source is arranged for emitting a continuous or pulse wave signal, and the detector is arranged for detecting an amplitude and a phase of the terahertz signal having interacted with the seed. A signal representing an outcome of the estimation may control a separator to separate seeds according to their estimated germination ability.

The invention claimed is: 
     
       1. An apparatus for estimating a germination ability of a seed, comprising:
 a terahertz signal source for generating a terahertz signal; 
 a support for holding the seed; 
 a detector for detecting at least part of the terahertz signal after the terahertz signal has interacted with the seed, wherein the detector detects an amplitude and a phase of the at least part of the terahertz signal that interacted with the seed, the detector including a detector output to output a detector output signal that is representative of the detected amplitude and phase of based on the detected at least part of the terahertz signal; 
 a data processing device for forming an image data from the detector output signal; and 
 a decision support system for providing an estimate of the germination ability from the image data. 
 
     
     
       2. The apparatus according to  claim 1 , wherein the terahertz signal is in a range of 0.01 to 10 THz. 
     
     
       3. The apparatus according to  claim 1 , wherein the data processing device combines the amplitude and phase data to form the image data of the seed. 
     
     
       4. The apparatus according to  claim 1 , wherein the terahertz signal source comprises a microwave signal generator for generating a microwave signal and an up converter, connected to an output of the microwave signal generator, for converting the microwave signal into a terahertz frequency band. 
     
     
       5. The apparatus according to  claim 1 , wherein the detector comprises a down-converter for converting the detected at least part of the terahertz signal having interacted with the seed into a microwave detection signal. 
     
     
       6. The apparatus according to  claim 1 , wherein the terahertz signal source and the detector are arranged for free space coupling with the seed. 
     
     
       7. The apparatus according to  claim 1 , wherein the decision support system:
 compares the image data of the seed with at least one reference image data stored by the decision support system; and 
 derives an estimation of the germination ability of the seed from the comparison of the image data of the seed with the at least one reference image data. 
 
     
     
       8. The apparatus according to  claim 1 , further comprising: a scanner for moving the support relative to the terahertz signal to provide a scan of the seed, wherein the data processing device forms the image data from the detector output signal as obtained for a plurality of positions during the scan of the seed. 
     
     
       9. The apparatus according to  claim 1 , wherein the terahertz signal source provides a synchronization signal to the detector, or vice versa, in order for the detector to operate in synchronism with the terahertz signal source allowing to perform a phase measurement by the detector. 
     
     
       10. The apparatus according to  claim 9 , wherein the generated terahertz signal is a continuous wave terahertz signal. 
     
     
       11. The apparatus according to  claim 1 , wherein the image data comprises multiple pixels associated with the respective detector output signals.